Optical systems such as stereomicroscopes are used in most diverse applications for generating a spatial image of an object of study. Such optical systems are employed in medical surgical microscopes for example, to inspect a surgical area.
The spatial image of the object of study is generated using the stereomicroscope which involves a representative from the instrument class of reflected light microscopes. The object of study is illuminated from the outside. Usually two optical paths are formed which are on their part equipped in each case with a lens system. The optical axes of both optical paths run through an arrangement of collecting lenses being upstream of the lens systems in direction of the object of study. Both the lens systems and also the collecting lens arrangement can comprise several optical lenses. The various optical lenses are used to adjust a focus as well as a zoom factor of the stereomicroscope. For this purpose, the lenses are displaced individually or in groups along the respectively assigned optical axis.
The displacement of optical elements for adjustment of the focus or for the adjustment of the zoom factor can be performed with the aid of motor-powered adjustment devices which relocate the optical element to a designated position along the optical axis. In contrast to the equally known displacement of optical elements by hand such motor-powered adjustment devices are controlled by the user with an operation device, for example a controller regulating the voltage- or power supply. As long as the user switches on the operation device, the lens is displaced along the optical axis. This movement is stopped by the user by switching off the operation device.
In document DE 103 23 629 A1, a gliding field linear motor is described with which optical elements, for example an optical lens, arranged in a sleeve, can be displaced along the optical axis. This is achieved using a magnetic gliding field moving along the optical axis. The magnetic gliding field and, thus, also the displacement positions of the optical elements are adjustable very accurately. The known gliding field linear motor supports the miniaturization of optical systems.